The inventive concept relates to semiconductor devices, and more particularly, relates to programming methods of magnetic memory devices.
The demand for nonvolatile semiconductor memory devices, which may be highly integrated and have large storage capacities, is increasing from with time. A representative example of a nonvolatile memory device is a flash memory, which is used in portable electronic devices. However, there active development in creating a nonvolatile element, which is randomly accessible and has improved performance. A representative example of such a nonvolatile element is a magnetic random access memory (MRAM) using a tunneling magneto-resistive (TMR) layer.
In general, a write error rate decreases in the case of increasing a write voltage upon performing a program operation on a MRAM. However, due to a manufacturing process issue, there is an increase in defective memory cells in which the write error rate does not decrease even though the write voltage is increased. With regard to defective memory cells, a decrease of the write error rate may be important to increase the quantity of memory devices manufactured (i.e., to increase the yield), as well as to improve the reliability of the memory devices.